Gear-wheel.



A. JOHNSTON.

GEAR WHEEL.

APPLICATION FILED MAR. 12,1908.

Patented Mar.8,1910.

aonnsmon, or o'rrunrwa, aowa.

- I GEAR-WHEEL.

cameos.

Specification of Letters Patent.

a I mac.

Application filed March 12, 130B. 1 Serial R0. @0390.

To all whom if'may concerns Be it known that it ALLEN JOHNSTON, of Ottumwa, Iowa, have invented a new and useful Improvement in Gear-Wheels, which invention is fully set forth in the following strip of sheet metal and fastening the same upon a suitable rim or other support, the fluting constituting the teeth of the gearwheel, and, in some cases, the flutings or bends have been tilled with elastic material. The result of these constructions has been that the gear-wheel is more or less elastic or yielding in character. 7

One of the prime objects of my invention is to provide a gear-wheel of this general character which shall be rigid, that is, in which neither the body of the wheel nor the teeth thereof shall yield or spring when in operation, thereby materially improving the accuraqy and smoothness with which said wheel acts, or a series of said wheels act,

upon each other. With this object in view, I take a strip of sheet-metal, preferably,

though not necessarily, in the-form of a closed integral ring, and preferablyof steel,

' and bend the same by means of dies, or any other suitable tool, to form the teeth of my gear-wheel. Preferably the teeth of the gear-wheel are formed from metal of such thickness that when the metal is bent sharply upon itself and the two adjacent surfaces brought together they will form a rigid tooth of the proper size. Instead of bend. ing the metal so that the adjacent surfaces of the metal constituting each individual tooth actually contact, I may, and sometimes do, employ a thinner sheet of metal and bend the'metal so that said surfaces do not contact, and then fill the intervening space with some solid, rigid and non-elastic material such as solder, for example, thereby se curing a solid, non-yielding, non-elastic construction. The toothed portion of the wheel being thus formed, the same is united to the interior or supporting body portion of the wheel in any manner suitable for securing a firm, rigid construction. For example,- in a smallwheel, a suitable rim or thimble whose external diameter that it may he slipped within the toothedfarnmh lus is insertedtherein and soldered, riveted or otherwise firmly secured thereto. With larger wheels, the interior body portien "of the wheel may be formed of oppositely disposed sheet-metal portions riveted together and clamped,,soldered or riveted to the annular toothed portion of the Wheel, said oppositely disposed sheet-metal portions tamstitutinga web with an axial opening for the wheel bearing orshaft. Or, if desired, the annular toothed portion may be mounted upon spokes extending radially from an annular central bearing portion of the wheel to said annular toothed portion and secured to the rim in any suitable manner, as it; soldering, riveting or clamping th thereto. 7

The inventive idea involved is capable of receiving a variety of mechanical expressions, some of which, for the 'purppse of,

illustrating the invention, are 1n accompanying drawings, in which-- Figure 1 is a side elevation, partly insection, showing a large and a small radially toothed gear-wheel made according to any invention, said wheels intermeshing; llii 2 is ahorizontal transverse section 'on'ther inc 2-2, Fig. 1; and Fig. '3 is a broken "side elevation, partly in section, illustrating a slightly different embodiment of theinventive idea. 7 I

Referring to the drawings in which like reference numerals indicate ike parts, 1 is the toothed annular portion'of the w'h here shown as formed from a closed ring of -sheet-metal, preferably sheet-steel, each of the teeth of said section being formed f bending'the metal upon itself so that its =ajacent surfaces contact, as'shown at2. This bending of the teeth so as to close the adjacent surfaces against each other may be effected bya die, or by the use of other suitable tools and, if desired, instead of being formed from a closed integral ring of sheet-metal, may be formed from a st or sheet-metal which is subsequently bent 'nrtu annular form. Tprefer, ilOWBVEI, to mu ploy theintegral ring as the blank from which the'toothed annular portion of the wheel is constructed.

As shown in Figs. 1 and 2, the interior body portion of the wheel is formed or composed of a web 3 of sheet-metal, which web is made up of two sheet-metal portions 4 and .5 secured together by rivets 6, 6. At the outer portion of said web the sheetmetal is bent at right-angles to the web 3, as shown at 7 and 8, and then has its extreme outer edges again bent at right-angles to the parts 7 and 8, thereby affording narnow flanges 9 and 10 which serve to clamp the toothed annular portion 1 between them. The toothed annular portion 1 is secured in place on the web portion either by. the clamping action of the flanges 9 and 10, or by solder, as shown at 11, Fig. 2, or, if desired, it may be secured by rivets (not shown). If deemed advisable, all three of these methods. viz., clamping, soldering and riveting may be employed.

Referring to Figs. 1, 2 and 3, 12 is a toothed annular portion of a wheel formed by bending sheet-metal upon itself, so that throu hout the greater portion of its extent the adjacent surfaces of the metal forming each tooth contact, or nearly contact, with each other, whilethe intervening space is filled by any suitable rigid material, as by solder 13, which solder may be employed not only to fill the intervening spaces, and thus render the wheel rigid, but may also serve to secure the toothed annular portion to an interior ring or body portion 14.

Instead of employing the web 3 of Figs. 1 and 2, or the ring 14, the wheel may be provided with spokes 15, Fig.3, extending from the axial portion of the wheel to the toothed. annular portion thereof, or preferably to an interior ring 16 suitably secured t(t) tlhe toothed annular portion, as by rive s Whether the Wheel is provided with the web 3, the ring 14, or the spokes 15, it has at its axis an opening for supporting 'it upon its-bearing. As here shown, the web construction and the spoke construction of Figs. 1, 2 and 3 are provided with ballbearings 18,- the ways for the bearings being provided by striking-up the interior edges of the web 3 or of theannular portion 19 to which the spokes 15 are secured, and said balls rest in a suitable race-way provided for them and within which the shaft, or other bearing for the wheel, is inserted. As here shown, the interior track or way for the ball-bearings 20 is composed in part of an inwardly projecting portion 21 of a plate 22 rovided with openings 23, by means of WlllCll said plate may be secured, as by screws, to any suitable supporting structure.

This entire plate is preferably of sheetmetal with the inwardly projecting portion 21 struck-up therefrom and clamping at its extreme inner edge 24 around the inner edge of a suitably formed sheet-metal plate 25 also forming a part of the interior portion of the race-way for the balls 20.

Instead of the ball-bearing structure shown in connection with the larger wheel in Figs 1, 2 and 3, the wheel may be keyed to a shaft or be mounted to turn upon a shaft, as stub-shaft 26, shown as the bearing for the smaller wheel at the right of each of said figures, the wheel being held .in place on said shaft in any suitable manner, as by a nut 27.

It will be observed that a wheel constructed as thus described may be made entirely of sheet-metal, such as sheet-steel, with teeth as accurately formed as the same would be if they were cut with an ordinary gear-cutter; that the interior portion of the wheel, whether composed of the ring or the web of Figs. 1 and 2, or the spoke construction of Fig. 3, can also be composed of sheetmetal, all of the parts being readily struck from the sheet-metal blanks and united by pressing, riveting, or otherwise By these means a wheel of great rigidity of construction is secured from cheap material, and at a minimum expenditure of time, money and power.

By bending the metal upon itself so that its adjacent portions contact, or, if they fail to contact, by filling the intervening space with a non-yielding, non-elastic material such as solder, a rigid construction is assured which will not give or ield under the stress of the work impose upon the wheel, thereby insuring smoothness and accuracy in the operation of the wheel.

While, for the purpose of illustrating the 10:

of sheet metal bent upon itself until its adjacent surfaces contact.

2. A toothed portion the teeth of which are composed of sheet metal bent upon itself until its adjacent surfaces contact, and a rigid body portion to which said toothed portion is secured.

3. A gear-wheel havin a sheet-metal toothed portion the teeth of which are comgear-wheel having a sheet-metal posed of sheet metal bent upon itself until the adjacent surfaces contact, and a sheetmetal body portion to which said toothed portion is secured.

v scribing witnesses.

ing raceway integral therewith, a sheetmetal rigid-toothed portion, and a rigid connection uniting said body portion and said toothed portion.

In testimony whereof I have signed this specification in the presence of two sub- ALLEN JOHNSTON. Witnesses:

L. E. STEVENS,

THos. E. Rononns. 

